Endoscopic suture placement tool

ABSTRACT

A surgical tool for endoscopic suture placement which permits a surgeon to place controlled and precise internal ligatures. The tool utilizes a drive rod including an articulating or deflecting portion. When forced to an extended position, the deflecting or articulating portion forms a hook or J-shaped needle, the tip of which can be used to accurately position the suture.

This is a continuation of application Ser. no. 08/292,088, filed Aug.17, 1994,. now U.S. Pat. No. 5,573,542.

FIELD OF THE INVENTION

This invention relates to medical devices used to place controlled andprecise internal ligatures. The device is particularly useful forendoscopic suture placement.

BACKGROUND OF THE INVENTION

During endoscopic surgery, precise placement of ligatures is required.Commonly, during endoscopic and other surgeries, sutures are placedusing any number of devices. However, such devices require extremedexterity and care on the part of the surgeon in order to reach thenecessary position without dropping the suture. Thus, it would bedesireable to identify a device which would permit a surgeon toprecisely place internal ligatures in a controlled manner.

SUMMARY OF THE INVENTION

Accordingly, the present invention is a ligature device including anouter sheath having a distal end, a drive rod slidably mounted to saidouter sheath for movement between a retracted position and an extendedposition, the drive rod including a deflecting portion having means forholding a ligature, the deflecting portion being at least partiallyconfined within the outer sheath and having a first shape when the driverod is in the retracted position, the deflecting portion extending fromthe distal end of the outer sheath and having a second shape when thedrive rod is in the extended position, the first and second shapes beingdifferent, and a movable actuator attached to the drive rod for movingthe drive rod between the retracted and extended positions.

In one form of the invention, the ligature holding means includes apassage extending inwardly from an outer surface of the deflectingportion, the transverse passage terminating at an eyelet.

In another form of the invention, the deflecting portion is made of ashape memory alloy.

In yet another form of the invention the device includes means forbiasing the drive rod toward the retracted position. Such biasing meanscan be a coil spring.

In a preferred form of the invention the first shape of the deflectingportion is substantially linear and the second shape is curved to form ahook or J-shape.

In order to promote stability, the outer sheath may include a hollowinterior having a square cross-sectional shape.

In another form of the invention, the deflecting portion is completelyhoused within the outer sheath when the drive rod is in the retractedposition.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood by reference to the appendeddrawings of which:

FIG. 1 is cross-sectional side view of a preferred embodiment of theinvention in its relaxed or rod retracted position;

FIG. 2 is an enlarged cross-sectional side view of the distal end of thedevice showing the position of the suture tip when the device is in arod retracted position; and

FIG. 3 is an enlarged cross-sectional side view of the distal end of thedevice showing the position of the suture tip when the device is in arod extended position.

DETAILED DESCRIPTION OF THE INVENTION

The apparatus of the invention is shown in detail in FIGS. 1-3.

Referring to FIG. 1, the endoscopic suture placement device of theinvention is shown in a side, cross-sectional view. As can be seen, thedevice is made up of an outer sheath or housing 1, which is an extended,tubular-shaped sheath on or in which the other components of the deviceare mounted. In the preferred embodiment shown, the length of the outerhousing will be approximately 450 mm, and will include a passage intowhich drive rod 2 is positioned. Housing 1 can be made of anystructurally adequate material which can be medically approved such asplastics, metals, composites, ceramics, and the like, as are well knownin the art. For structural purposes, and to ensure that drive rod 2 doesnot twist when in use, it is preferred that the cross-section of thepassage in which the drive rod 2 is positioned is square or diamondshaped. Likewise, the cross-section of drive rod 2 will match that ofthe passage through the housing. Generally, the length of a side of thediamond-shaped cross-section of drive rod 2 will be from about 1-2 mm.The passage will, of course, be slightly larger to accommodate movementof the drive rod.

Movement of drive rod 2 from the rod retracted position shown in FIGS. 1and 2 is accomplished using hand actuator 3, which, as seen in FIG. 1,consists of three finger/thumb rings, though many differenthandle/actuator configurations are possible. In use, the surgeon willgrasp the device using finger/thumb rings in the same manner as holdinga syringe. A spring 4 is mounted surrounding a proximal portion of driverod 2 and supported within housing 1 to bias the rod to a retractedposition.

The fourth key component of the invention is a deflecting portion 5 ofdrive rod 2 positioned at the distal end of drive rod 2 and betweendrive rod 2 and a suture tip 6.

Deflecting portion 5 is preferably formed from a filament of shapememory alloy (SMA), such as Ni/Ti alloy. SMA of the type useful in thepresent invention is available from Shape Memory Applications, Inc. ofSunnyvale, Calif., under the name NiTi Super Elastic Wire Cr-Dp. Itshould be recognized, however, that many other materials can be used, solong as they meet the performance requirements for the deflectingportion, i.e. that they will form an "arc" when extended from thehousing by motion of the actuator, so that the surgeon gains theadvantage of being able to place the suture underneath the tissue bypulling the device back toward him or her.

Labels in FIG. 2 indicate the same components as in FIG. 1. Also, as inall views, components are shown as spaced from one another for clarityand are not to scale. As can be seen, suture eyelet 7 is shown in FIG.2.

FIG. 3 shows an enlarged cross-sectional view of the distal portion ofthe device when drive rod 2 is in its extended position. In thisposition, deflecting portion 5 returns to its "memorized" curved orhooked configuration, thereby forming a J-shaped hook at the distal endof the device.

In use, the surgeon will first position a suture in suture tip 6,secured in suture eyelet 7, then position the tip at the desiredposition in the patient's body, force the tip to the extended J-shapedconfiguration, which forces the suture tip and suture through thedesired tissue. Suture placed laparoscopically requires the ability topenetrate multiple tissue planes with precise control. The device of theinvention provides this action through the use of the describedembodiments.

The invention can be used for many different kinds of proceduresincluding, but not limited to, laparoscopic hysterectomy, laparoscopicBirtch and laparoscopic Nissan procedures.

Although only the most preferred embodiment of the invention has beenshown and described. Many modifications and rearrangements of thecomponents of the invention, which nevertheless include the key featuresthereof, will be apparent to those skilled in the art. Thus, suchmodifications are considered to be within the scope of the appendedclaims.

What is claimed:
 1. A surgical tool including:a tubular, elongatedhousing having a proximal end, a distal end, and a passage defining arod axis therethrough; a tissue piercing tip including means forsupporting a ligature; a suture tip drive rod positioned within saidpassage, and moveable along the length thereof from a drive rodretracted position, wherein the tissue piercing tip is coaxial with thetip drive rod, to a drive rod extended position; and deflecting meanscomprising a shape memory portion secured on a first end to a distalportion of said drive rod and on a second end to said tissue piercingtip for deflecting said tissue piercing tip from said axis when said rodis in said extended position.
 2. A surgical tool including:a tubularhousing having a proximal end, a distal end, and a passage defining arod axis therethrough; a tissue piercing tip portion including a meansfor supporting a ligature; a tip drive rod positioned within saidpassage, and moveable along a length thereof from a drive rod retractedposition, wherein the tissue piercing tip is coaxial with the tip driverod, to a drive rod extended position; and deflecting means comprising ashape memory portion secured on a first end to a distal portion of saiddrive rod and on a second end to said tissue piercing tip for causingsaid portion, in combination with said tip, to form a J-shaped hook whensaid drive rod is moved to said extended position.
 3. The surgical toolof claim 2 wherein said means for supporting a ligature comprises aneyelet shaped to carry a ligature.
 4. A surgical tool including:atubular housing having a proximal end, a distal end, and a passagedefining a rod axis therethrough; a tip portion having a tissue piercingend and a connecting end, and including an opening capable of carrying aligature; a tip drive rod positioned within said passage, and moveablealong a length thereof from a drive rod retracted position, wherein thetissue piercing end is coaxial with the tip drive rod, to a drive rodextended position; and a deflecting portion secured on a first end tosaid drive rod and on a second end to said connecting end of said tipfor causing said portion to form an arc of substantially semicircularshape and to cause said tissue piercing end of said tip portion in adirection toward said proximal end of said housing when said drive rodis moved to said extended position.
 5. A surgical tool including:a rigidtubular housing having a proximal end, a distal end, and a passagedefining a rod axis therethrough, wherein said tubular housing is fixedrelative to said rod axis; a tissue piercing tip including means forsupporting a ligature; a suture tip drive rod positioned within saidpassage, and moveable along the length thereof from a drive rodretracted position, wherein the tissue piercing tip is coaxial with thetip drive rod, to a drive rod extended position; and deflecting meanscomprising a shape memory portion secured on a first end to a distalportion of said drive rod and on a second end to said tissue piercingtip for deflecting said tissue piercing tip from said axis when said rodis in said extended position.
 6. A surgical tool including:a tubularhousing having a proximal end, a distal end, and a passage defining arod axis therethrough; a tissue piercing tip portion including a meansfor supporting a ligature; a tip drive rod positioned within saidpassage, and moveable along a length thereof from a drive rod retractedposition to a drive rod extended position, wherein said tissue piercingtip is substantially contained within said tubular housing when said tipdrive rod is in said retracted position; and deflecting means comprisinga shape memory portion secured on a first end to a distal portion ofsaid drive rod and on a second end to said tissue piercing tip forcausing said portion, in combination with said tip, to form a J-shapedhook when said drive rod is moved to said extended position.